The properties of low-density polyethylene (LDPE) and its blend with linear low-density polyethylene LDPE:LLDPE (75:25) modified with varying concentrations of dicumyl peroxide (DCP) were compared. Chemical modification was carried out in a Brabender plasticorder under set conditions of temperature, rotor speed, and time. The results are reported in terms of the type of polyethylene used, concentration of DCP, mixing torque, temperature and time on the processing, and mechanical and physical properties of the modified samples. Interpretation of the results is given in terms of gel contents which relate to the three-dimensional network structure of polyethylene. The modified blend forms a denser network structure and, hence, better product properties relative to that of modified LDPE, indicating the influence of LLDPE in increasing the rate and extent of crosslinking on blending with LDPE.